Drum inserter



April 24, 1962 Filed May 12,

J. RABINOW ET AL DRUM INSERTER 2 Sheets-Sheet 1 E @(o O) INVENTORS Jacob Rab/now Harold J. Rosenberg Z4 g 72 g ATTORNEY United States Patent 3,031,062 DRUM INSERTEIR Jacob Rabinow, Tahoma Park, and Harold J. Rosenberg,

Siiver Spring, Md., assignors, by direct and mesne assignments, to Rabinow Engineering (10., Inc, Rocirviile,

Filed May 12, 1960, Ser. No. zasrs 14 Qlaims. c1. 193-63) This invention relates to article feed devices and more particularly to high-speed letter feeders.

There is a current need for a reliable high-speed device for inserting articles onto or into a movable receiving device. For example, U.S. Patent 2,901,089 discloses a mechanical coding and sorting device which is principally useful in sorting letter mail. An inserter constructed in accordance with our invention has been advantageously used for inserting letters into the pockets of the sorting device disclosed in that patent. Further, another possible application of our invention is in connection with the multiple operator sorting system disclosed in pending application Serial No. 32,003 filed on May 26, 1960 and assigned to the assignee of this application. These are two specific examples of equipment which could advantageously use the inserter of our invention, though it is to be understood that the lIlSCl'llCl may be used in connection with numerous other types of equipment where there is a need to rapidly and accurately insert articles.

Accordingly, an object of the invention is to provide a general purpose inserter having particular, although not exclusive, application in connection with mail sorting equipment.

Briefly, a preferred form of the invention has a rotary drum with a central passageway along the axis of rotation. A numbe of annularly spaced slots open through the outer surface of the drum and communicate with the central passageway in order to receive and direct articles such as letters. By having the drum positioned adjacent to the receptors of the articles (letter receptors in a given instance) the rotation of the drum may be timed with the translation of the pockets so that as the drum turns, each pocket is emptied, one by one, into the moving receptors.

. Our drum inserter has proven to be very reliable and is especially good in handling letter mail since the slots in which the letter mail passes may be made sufficiently wide to handle practically all letter mail regardless of its thickness (within wide practical limits), its condition as to degree of mutilation, and other variables such as texture ordinarily encountered in machine handling letter mail on a high volume basis.

One of the features of the invention is in the configuration of each slot. The slot has a comparatively wide inlet and narrow outlet and is defined by a pair of spaced dividing walls or panels. One wall is concave in the direction of rotation of the drum to provide a guiding function for a letter as it is entering the slot and to allow ample space beyond the faces of the letter as it is being discharged. This aissures that a letter entering a given slot will slide freely into the slot, and will eliminate the chances of binding against the walls of the slot as the letter enters a moving receptor.

Other objects and features of importance will become apparent in following the description of the illustrated form of the invention. It is understood that the illustration merely exemplifies the principles of the invention and one possible use thereof.

FIGURE 1 is a fragmentary side elevational view showing the drum inserter in use.

FIGURE 2 is a cross-sectional view taken approximately on the line 22 in FIGURE 1.

FIGURE 3 is a fragmentary perspective view of the drum inserter.

FIGURE 4 is a schematic view showing the principle of operation of the invention.

"FIGURE 5 is a schematic top View of the feeder.

In the accompanying drawings, rotary feeder 9 is shown operatively connected with fragmentary illustrated sorting machine 11. As previously indicated, the sorting ma chine may be similar to the machine disclosed in US. Patent No. 2,991,089 or may be some other type of sorting machine or equipment. Therefore, machine 11 merely diagrammatically illustrates one possible use of rotary feeder drum 10. Machine 11 has a suitable frame 12 supporting endless conveyor chains 13 and 14 to which trays 15 are secured. Each tray has a number of upwardly opening compartments 16 into which letters L are dropped by drum 10 of feeder 9.

Drum 10 has two ends or end walls 17 and 18 provided with central apertures 12. Annularly spaced radial slots 20 are formed in the drum, and the inner ends of the slots are in registry with passageway 21, while the outer ends of the slots open through the peripheral surface area of the drum. Passageway 21 entends completely through the drum and is concentric with the axis of rotation of the drum.

Each slot 20 is defined by a pair of spaced plates 22 and 23 which extend from passageway 21 to the periphery of the drum. Plate 23 is essentially a flat plate, but plate 22 is concave in the direction of rotation of the drum. Structurally, plate 22 is one of a pair of plates 22, 24 joined together at an apex 25 and diverging outwardly toward the periphery of the drum. Plates 22 and 24 are so arranged with respect to each other that they include a dihedral angle. Plate 23 is also one of a pair of plates identical to the pair 22, 24. Accordingly, the plates co-operate to form means dividing the part of the drum from the passageway 21 to the periphery of the drum, into letter receiving, guiding and discharge slots 29.

The side edges of the plates may be secured to ends 17 and 18 by suitable fasteners, for example (FIGURE 3) tabs 27 fitting in holes 28 in the ends 17 and 13 of the drum. Transverse stay bolts 29 are attached to the ends 17 and 18 of the drum and are located between adjacent slots 24 to hold the drum assembled as a rigid unitary structure.

Drum 10 is peripherally supported for rotation by a plurality of wheels 36 rotationally mounted on transverse spindles 31 which are fixed to frame 12 above compartments 16. The wheels are either grooved or flanged so that the circular edges of plates 17 and 18 seat therein and prevent drum end play. Although the number of wheels 30 may be increased or decreased, four such wheels are satisfactory with a pair of the wheels being lower wheels and the remaining wheels being upper wheels (FIGURE 1).

Sorting machine 11 is equipped with chains 13 and 14, and therefore, one of the chains 13 is used to drive drum 10 so that its rotational movement is synchronized with the linear movement of trays 15. The actual configuration of the driving means may be varied and therefore the sprockets, chains and shafts are given as an example of a typical drive connection between the drum and the chain 13. These means are composed of sprocket 33 secured to spindle 34, and the spindle is mounted for rotation in a bearing carried by frame 12. Sprocket 35 is secured to the same spindle and has a chain 36 enmeshed therewith. By having sprocket 33 engage chain 13, the chain 36 will move at a rate proportional to the movement of chain 13.

Spindle 37 is mounted in a bearing attached to frame 12 and has sprocket 38 with which chain 36 is enmeshed, together with sprocket 39 secured thereto. Drive chain 49 is engaged with sprocket 39 and with sprocket 41 which is secured to end 18 of drum 10. Since the drum '31 sets in frame 12 (FIGURE 2) and sprocket 41 is located on the outside of a part of the frame, sprocket 41 is set off from the outer face of end 18 by bolts 42 which are secured to sprocket 41 and to end 18 of drum 10.

Drum passageway 21 may be fed by hand, or by using a conventional feeder (not shown) or by a special feeder P if the advantages of precise, timed drum-feeding is desired. Feeder F is composed of a conveyor which moves letter L into passageway 21 to an unloading station at which a group of pusher fingers 46 push the letter off of a letter supporting shelf 47 so that it drops into one of the slots 20 (FIGURE 1). Baflle 48 is located alongside of the fingers "46 making sure that the letter does not turn over or tilt too far when it is moved by fingers 46.

The fingers 46 are secured to shafts 49 which are timed to rotate with the rotation of drum 10. This can be accomplished in many ways, one of which is to couple shafts 49 with a belt or chain drive 50 and operate the drive from a shaft that rotates at a speed proportional to the speed of the drum, e.g. see the dotted line in FIGURE 1.

A stationary guide 51 is mounted beneath a part of the drum, and the lower edge of a letter rests on the guide when the letter is inserted in a slot. FIGURE 4 shows this action where the letter L has entered slot 20 and is being swept by drum along the surface of guide 51. As the drum rotates, compartment 16 moves to position 16 and slot moves to position 20, between which the lower edge of the letter slips off guide 51 and begins to enter compartment 16. The significance of the curvature of one side of the slot is evident at positions 16 and 20'. There is ample clearance, especially for large letters, to allow the letter to move freely into the compartment at 16' without binding.

Each slot has a wider inlet than outlet (FIGURE 4) and the slot outlet is narrower than the compartment inlet. The peripheral speed of the drum is equal to the speed of tray 15, but the slot inlets are located radially inward of the drum periphery. Therefore, the linear speed of the drum at the slot inlets is smaller than the speed of the drum periphery, and this creates a favorable timing condition for feeding letters into the slots. If a slot inlet is twice as wide as its outlet and the linear speed of the inlet is slower than the speed of the outlet (depending on the radial inward distance) this will present the slot inlet to the incoming letter for a comparatively long time having the effect of a slot inlet-to-outlet Width ratio much greater than the geometric 2 to 1.

Various changes and modifications may be made without departing from the protection afforded by the scope of the following claims.

What is claimed is:

1. In combination with a device providing a succession of individual fiat articles which are fed one-by-one, a rotary feeder for inserting the individual articles edgewise into moving compartment inlets, said feeder comprising a rotary drum having an outer periphery located adjacent to the compartment inlets, said drum provided with a central passage concentric with the axis of rotation of the drum, one end of said drum having an article entrance opening registered with said passage and through which the succession of individual articles passes, means dividing the portion of the drum from the passage to the periphery into article guiding and discharge slots which are narrower than the length and the width of the fiat articles and which open through the periphery of the drum to direct articles edgewise and one-by-one from said passage into the compartment inlets, and means for driving said drum at a speed so that the peripheral speed of the drum is equal to the speed of the moving compartments.

2. The rotary feeder of claim 1 wherein there is a fixed guide adjacent to the periphery of the drum at one section thereof to prevent the articles from prematurely sliding out of said slots, and said guide terminating adjacent to the compartment into which the article in a particular slot is to be discharged, and one wall of each slot being concave in the direction of travel of the drum to provide clearance for the fiat article as it is being discharged into a compartment during the rotation of said drum.

3. In a rotary feeder for inserting individual fiat articles into moving compartment inlets, a rotary drum having an outer periphery located adjacent to the compartment inlets, said drum provided with a central passage concentric with the axis of rotation of the drum, one end of said drum having an article entrance opening registered with said passage, means dividing the portion of the drum from the passage to the periphery into article guiding and discharge slots which open through the periphery of the drum to direct articles from said passage into the compartment inlets, said slots being narrower than the length and width of each fiat article to require the articles to enter and leave the slots edgewise of the articles, said dividing means comprising a plurality of annularly spaced plates joined in pairs with the plates of a pair forming a dihedral angle therebetween and having an apical edge defining a portion of the surface of said passage.

4. The rotary feeder of claim 3 wherein the outlet of each slot is narrower than said moving compartment inlets whereby small differences in position or velocity do not prevent the article from passing from a slot into an inlet.

5. The rotary feeder of claim 3 wherein one plate of each pair is concave in the direction of drum rotation to present a curved surface to the articles entering and leaving said slots.

6. A rotary feeder comprising a drum having a central article receiving passage, means forming article discharge slots opening through the outer periphery of the drum and registered with said passage, the ends of said slots which are registered with said passage being wider than the slot ends which open through said drum periphery, each slot having a pair of opposing surfaces, and one of said surfaces being curved to guide the leading edge of the article entering the slot and provide clearance for the article as it is leaving the end of the slot which opens through the periphery of said drum.

7. In a rotary feeder for inserting individual articles into moving compartment inlets, a rotary drum having an outer periphery located adjacent to the compartment inlets, said drum provided with a central passage concentric with the axis of rotation of the drum, one end of said drum having an article entrance opening registered with said passage, means dividing the portion of the drum from the passage to the periphery into article guiding and discharge slots which open through the periphery of the drum to direct articles from said passage into the compartment inlets, and article feeding means in said passage to feed individual articles into successive slots in time with the rotation of said drum.

8. The rotary feeder of claim 7 wherein said article feeding means include a shelf to support a letter, and pusher means adjacent to said shelf to push the letter off the said shelf by contacting a face of the letter.

9. The combination of claim 7 wherein the slot inlets are wider than the slot outlets.

10. A rotary feeder comprising a drum adapted to be rotated in a given direction, said drum having an article receiving passage at the axis of rotation of the drum, means forming article receiving and discharge slots in the drum, each slot having an inner end registered with said passage and an outer end opening through the periphery of the drum, the inner ends of said slots being wider than the outer ends of said slots, each slot having a forward surface and rear surface with reference to said given direction of rotation of said drum, and said forward surface being concave in the direction of rotation of said drum to provide-clearance for an article as it leaves a slot during rotation of the drum.

1.1. In an article feeding system, a plurality of movable compartments, a rotary structure, and means to synchronize the rotation of said structure with the movement of said compartments, said rotary structure having an article passage at the axis of rotation thereof, an article feeder to feed articles in said passage one by one, means defining article slots in said structure with the inlet ends of said slots registered with said passage and the discharge ends of said slots opening through the periphery ofsaid structure adjacent to said compartments, and said inlet ends of said slots being wider than said discharge ends thereof.

12. A drum inserter to insert letters individnually into individual moving compartments, said drum inserter comprising a drum having a pair of end members, a plurality of walls extending axially between said end members, pairs of said walls cooperating to form slots which open through the periphery of said drum, said slots being narrower than the length and Width of the letters to require the letters to be received and discharged end wise through said slots, the inner edges of each pair of walls terminating short of the central axis of the drum to define a central inlet passage for the letters, said inner edges of said pairs of walls being joined at an angle to form a guide for the edges of the letters as they move from said central inlet passage into the slots, said slots having inner ends of a greater width than their outer ends to allow ample time for a letter to enter a slot and by gravity dropped into the slot as the drum rotates, with the letter accelerating as it passes through said slot, and the Walls of the slot guiding the letter due to the drum rotation toward a moving compartment.

13. The subject matter of claim 12 wherein said slots have outlet ends of a smaller width than the inlets of said compartments to provide tolerance for the entry of the letter into a compartment.

14. The inserter of claim 13 wherein one wall of each slot is concave in the direction of drum rotation to provide clearance for the discharge of a letter therefrom into a moving compartment.

References Cited in the tile of this patent UNITED STATES PATENTS 1,127,520 Rosen Feb. 9, 1915 1,815,321 Martin July 21, 1931 2,373,183 Hawthorne Apr. 10, 1945 

